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Discussion Starter #1 (Edited)
Long story short it was burning oil so I got a rebuild done. All was good after the build I was getting 21.5psi of boost with my TMIC. I upgraded to an ETS FMIC all was good for 2-3 weeks then I noticed it only made 17-18psi of boost. I did a boost leak test and all good. Replaced bpv gasket. And still no luck. I need to talk to my tunner but this covid stuff has him unavailable.
It's a 2011 STI wagon
IAG stage 2 tuff block
ID1050
Invidia turbo back with cat
AEM pump
16g turbo( Should have gone bigger)
ETS front mount.
Dyno tuned by muscle motor sports Reno NV.
 

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Peak boost should not be, and is not a constant. Weather/temp is a significant factor. It has gotten warmer?

Do you have an issue? I don't know.

Out of curiosity what was you mileage when your (re) built?
 

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Discussion Starter #3
Peak boost should not be, and is not a constant. Weather/temp is a significant factor. It has gotten warmer?

Do you have an issue? I don't know.

Out of curiosity what was you mileage when your (re) built?
I did a rebuild at 64k.
It used to hold 21 from 3200-5000. The weather is the same. On my logs the intake temps have a 2 degree delta.
 

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I did a rebuild at 64k.
It used to hold 21 from 3200-5000. The weather is the same. On my logs the intake temps have a 2 degree delta.
Assuming nothing otherwise has changed. When you did the boost leak test was your bpv still connected to the inlet? It is possible to leak past. How did you test it? evap smoke it, soap and water while you air pressurized the system? What psi did you pressurize it to >18? If you don't you might not be able to replicate.

Manual boost gauge available?

Are you using tbolt clamps on all your ic piping?

You could tempoarily block off the bpv and try and see if that changes anything.

What ebcs are you using? That could have gone bad as well. I think you can see wastegate requested vs actual duty cycle on cobb AP might give a hint here as well. Isn't the stock spring pressure on a 16g 16ish psi? I'm not going to tell you to do it. But you could change the vac to the turbo wg. Do a short and I do mean short pull like this to see if you break the 17psi mark.

Just trying to give you other ideas to look for.

Steve
 

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Discussion Starter #5
Assuming nothing otherwise has changed. When you did the boost leak test was your bpv still connected to the inlet? It is possible to leak past. How did you test it? evap smoke it, soap and water while you air pressurized the system? What psi did you pressurize it to >18? If you don't you might not be able to replicate.

Manual boost gauge available?

Are you using tbolt clamps on all your ic piping?

You could tempoarily block off the bpv and try and see if that changes anything.

What ebcs are you using? That could have gone bad as well. I think you can see wastegate requested vs actual duty cycle on cobb AP might give a hint here as well. Isn't the stock spring pressure on a 16g 16ish psi? I'm not going to tell you to do it. But you could change the vac to the turbo wg. Do a short and I do mean short pull like this to see if you break the 17psi mark.

Just trying to give you other ideas to look for.

Steve
I did and external air test at 20psi with soapy water and my ear. I have a defi gauge that reads the same as the logs. The intercooler has t bolt clamps and pressure checks good. I talked to my tuner today he gave me a new map with a higher waste gate cycle. Boost went up 1.5 psi. I ordered a grimmspeed 3 port and will get him to tune it when I get it. If this doesn't fix it I'm convinced the bypass valve is failing.
 

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Discussion Starter #6
Fixed. Booster controller failed. I upgraded to a 3 port grimmspeed and put down 370 awhp 390tqs
 
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